"You can change your reservation online if your: Travel was booked on aa.com or through American Airlines Reservations Travel was booked by a travel agent or travel website (may require changes through the original booking source – check with travel agent or the website) Travel originates within the U.S. Trip isn't an AAdvantage award, booked with a promotional code or part of a group booking Have at least 3 hours before your next scheduled flight You can access your reservation from “My trips/check in” on the homepage or go to ""Find reservations"". After you retrieve your reservation, look for the “Change trip” option. Find a reservation If your reservation doesn’t have the “Change trip” option, contact Reservations. Contact Reservations More info: <a>https://airlinesreservationsdeals.com/flight-change/</a> <a>https://en.wikipedia.org/wiki/Flight_rules</a>"